Accelerated Share Repurchases, Settlement (Payment) or Receipt, Shares

No definition available.

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- Definition

Expiration date for the authorization to repurchase up to $1 billion.

+ References

No definition available.

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- Definition

Number of shares of common stock that were repurchased in the administration of our employee share-based compensation plans. Under the terms of these plans, we accept shares of common stock from option holders if they elect to surrender previously-owned shares upon exercise of the option to cover the exercise price of the options or, in the case of restricted shares of common stock, the withholding of shares to satisfy tax withholding obligations associated with the vesting of such shares.

+ References

No definition available.

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- Definition

Cost of common stock that were repurchased in the administration of our employee share-based compensation plans. Under the terms of these plans, we accept shares of common stock from option holders if they elect to surrender previously-owned shares upon exercise of the option to cover the exercise price of the options or, in the case of restricted shares of common stock, the withholding of shares to satisfy tax withholding obligations associated with the vesting of such shares.

+ References

No definition available.

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- Definition

Treasury Stock, Decrease In Capital In Excess Of Par Value

+ References

No definition available.

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- Definition

Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 25

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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- Details

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- Definition

Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

+ References

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- Definition

Equity impact of the value of treasury stock (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

+ Details

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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Stockholders' Equity - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended		1 Months Ended	0 Months Ended		6 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Apr. 30, 2015	Mar. 13, 2015	Nov. 10, 2014	Mar. 13, 2015	Dec. 31, 2014	Aug. 31, 2014	Nov. 07, 2014	Sep. 30, 2014	Apr. 28, 2015	Apr. 30, 2014	Apr. 30, 2013
Equity, Class of Treasury Stock [Line Items]
Dividends per common share (in dollars per share)	$ 0.28	$ 0.27
Share repurchase authorization								$ 1,000,000,000
Remaining authorized amount								816,000,000
Shares repurchased in open market	0.10us-gaap_TreasuryStockSharesAcquired	0.10us-gaap_TreasuryStockSharesAcquired
Value of shares repurchased	26,000,000	11,000,000
Common shares acquired in connection with employee stock plans, shares	0.2	0.4
Common shares acquired in connection with employee stock plans, amount	40,000,000	38,000,000
Treasury stock reissued (shares)	0.7
Treasury stock reissued	39,000,000
Accumulated other comprehensive income	227,000,000						223,000,000
Net unrealized gains on our investment securities
Equity, Class of Treasury Stock [Line Items]
Accumulated other comprehensive income	331,000,000						301,000,000
Additional liability that would exist on closed block of long-term care policies assuming unrealized gains on investments backing such products were realized and reinvested at current yields
Equity, Class of Treasury Stock [Line Items]
Accumulated other comprehensive income	104,000,000						78,000,000
Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Dividends per common share (in dollars per share)			$ 0.29
Accelerated Share Repurchase Agreement
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization									500,000,000
ASR, shares received				0.36
Shares repurchased in open market					3.06	3.42
Decrease in capital in excess of par value					100,000,000
Value of shares repurchased					400,000,000	500,000,000
Shares repurchased in open market, average price						$ 146.21
September 2014 Share Repurchase Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization										2,000,000,000
Expiration date of new authorization	Dec. 31, 2016
Shares repurchased in open market	0.10	0
Value of shares repurchased	26,000,000	0
September 2014 Share Repurchase Authorization \| Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Remaining authorized amount											1,230,000,000
Shares repurchased in open market			0.63
Value of shares repurchased			112,000,000
April 2014 Share Repurchase Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization												1,000,000,000
Shares repurchased in open market	0	0
Value of shares repurchased	0	0
April 2013 Share Repurchase Authorization
Equity, Class of Treasury Stock [Line Items]
Share repurchase authorization													1,000,000,000
Shares repurchased in open market	0	0.10
Value of shares repurchased	$ 0	$ 11,000,000